RH033 Exam Dumps : Red Hat Linux Essentials

The bg utility resumes suspended jobs from the current environment by running them as background jobs if job control is enabled. If the job specified by job_id is already a running background job, the bg utility will have no effect and shall exit successfully. Using bg to place a job into the background will cause its process ID to become "known in the current shell execution environment", as if it had been started as an asynchronous list.

Answer option D is incorrect. The fg utility continues a stopped job by running it in the foreground, some shells are not able to run this command.

Syntax:

fg [%job] Where %job specifies the job that a user wants to run in the foreground.

Answer option A is incorrect. The jobs command lists the jobs that are running in the background and in the foreground. If the prompt is returned with no information, no jobs are present.

Syntax: jobs [-p | -l] [-n] [-p] [-x] [job id]

Some important options used with jobs command are as follows:

Answer option C is incorrect. The top command is used to produce a frequently-updated list of processes. By default, the processes are ordered by percentage of CPU usage, with only the "top" CPU consumers shown. This command shows how much processing power and memory are being used, as well as other information about the running processes. The following figure demonstrates the output of the top command:

The rm *[0-9] command deletes all files whose names end with a number.

Answer option B is incorrect. The rm [^0-9] command deletes all files except those having names ending with a number.

Answer option C is incorrect. The rm ^[0-9] command deletes all files whose names begin with a number.

Answer option D is incorrect. The rm [0-9]* command also deletes all files whose names begin with a number.

The scp command is used to copy files from one host to another over the network.

What is the scp command?

The scp command is used to copy files over ssh connections. This is pretty useful if a user wants to transport files between computers, for example, to backup a file. The scp command uses the ssh command to copy files over the network.

Syntax:

# scp [options] source destination

Where, source refers to the file which a user wants to copy from his current computer/directory, and destination refers to the home directory of the remote system where a user wants to copy the file.

Some important options used with the scp command are as follows:

Answer option A is incorrect. The ls command in Linux lists information about files (the current directory by default).

Answer option C is incorrect. The mutt command is used to manage email within a text only environment.

Answer option B is incorrect. The cat command is used to join multiple files together and display the result on the screen.